Notices
Series I Tech Garage The place to discuss anything technical about the RX-8 that doesn't fit into any of the categories below.

Possible New Renesis Engine Failure Theory?

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old 01-10-2011, 05:02 PM
  #1  
SARX Legend
Thread Starter
iTrader: (46)
 
9krpmrx8's Avatar
 
Join Date: Jan 2007
Location: San Antonio, Texas
Posts: 33,784
Received 452 Likes on 366 Posts
TX Possible New Renesis Engine Failure Theory?

Okay, rather than bump my thread on my OMP issue I figure this needed it own thread.

History:

My first engine was replaced at 22k, second at 96k. First saw no premix really and the second only for a pretty short period of time. Both saw 3,000 mile oil changes and regular maintenance otherwise as well.

My third and current motor has had the BHR Ignition, BHR Fuel PUMP, SOHN adapter, Catless midpipe, and has been premixed since break in.

Keep in mind that your OMP lines, oil injectors, etc. are all transferred from one motor to the next. So in my case, they were moved twice.

I actually noticed after some time that my second engine started to use less oil than it had previously (usually used about a quart every 3k) but after some research I determined that every engine seemed to be a bit diff due to driving habits. etc. So I didn't really worry about it too much. At that time, I commuting 70 miles a day, all highway. Well, I got divorced, moved a couple miles form work and my driving habits changed greatly. Then for the next two years I drove shorter distances but still noticed my oil consumption remained low. A while after that, my second engine lost compression.

Then I got my current (3rd) engine. In the beginning the 1 QT SOHN reservoir would empty fairly quickly and I was running about 1/2oz per gallon of premix. But then I noticed after a long trip that my SOHN reservoir level didn't seem to move at all. I checked the lines, the SOHN, etc. and all seemed well except a slight leak on the reservoir hose. No CEL for the OMP, nothing seemed out the ordinary. Either way, I started premixing 1oz per gallon just to be safe on my new motor.

The months went by, the SOHN reservoir use was still low. So, I talked to Richard Sohn and he told me a SOHN adapter has never failed so I considered replacing the OMP even though there were no CEL's, etc. I talked to some others here that I trust and still really didn't have an answer and didn't want to pay for a new OMP if I didn't need it. I wasn't in a rush because it was using some (very little) oil from the reservoir and I guessed that 1oz per gallon of premix in the gas should keep any damage to the seals from happening.

Well, finally I decided to suck it up and dig into it. I bought new OMP lines and oil injectors. I found that two of my OMP lines were clogged and basically falling apart as well. The rear oil injectors were filthy compared to the front and one failed the vacuum test.







So, basically my engine would have died eventually due to the lack of oil being injected had I not been premixing so heavy. My new theory is that many engines are dieing due to this and people are not even aware that this is the cause.

So if you do not monitor your oil consumption, you may be in trouble as your oil injectors and OMP lines deteriorate. It has also been noted also that an OMP can fail without triggering a CEL or putting the car in limp mode like it should.

So, for all of you with decent mileage, I suggest replacing your OMP lines and oil injectors as a preventative measure. But keep in mind that it is kind of a bitch to replace those items.



Edit: Since Christmas, As of today, I have gone through a quart in 749 miles (includes road trip to my parents).

Last edited by 9krpmrx8; 07-09-2014 at 12:00 AM.
Old 01-10-2011, 05:11 PM
  #2  
Registered User
iTrader: (2)
 
terch1's Avatar
 
Join Date: Feb 2008
Posts: 1,317
Likes: 0
Received 2 Likes on 2 Posts
I removed and inspected mine when I installed the Sohn adapter. I removed the omp and lines and soaked the lines in degreaser for a couple days. This cleaned them up pretty good. But they really didn't look bad in the first place. Mine, fortunately, looked nothing like yours. But this is something that people should monitor. Clogged omp lines = no bueno!
Old 01-10-2011, 05:25 PM
  #3  
SARX Legend
Thread Starter
iTrader: (46)
 
9krpmrx8's Avatar
 
Join Date: Jan 2007
Location: San Antonio, Texas
Posts: 33,784
Received 452 Likes on 366 Posts
Man, you are ambitious. This is not something I would do just to check things

For the price it's easier to just replace everything. I actually wish I could have done my injectors at that time but it was Christmas and I was low on funds. My fuel injectors have 120k on them as well so i am planning to get them cleaned and bench tested.
Old 01-10-2011, 05:38 PM
  #4  
Drummond Built
iTrader: (6)
 
WTBRotary!'s Avatar
 
Join Date: Aug 2008
Location: DFW, Texas
Posts: 3,703
Likes: 0
Received 0 Likes on 0 Posts
^^^ This is something Id love to do since I just got a new engine. Is it hard, im curious because I want to see how mine are doing with this new engine. I might have to take a trip down to ole' San Antonio and get some help.

At anyrate with your new OMP and lines did your Sohn start to move again? Did you start to use more oil?
Old 01-10-2011, 05:56 PM
  #5  
SARX Legend
Thread Starter
iTrader: (46)
 
9krpmrx8's Avatar
 
Join Date: Jan 2007
Location: San Antonio, Texas
Posts: 33,784
Received 452 Likes on 366 Posts
Come on down. Oh, and yes, glad you said that.

Edit: Since Christmas, As of today, I have gone through a quart in 749 miles (includes road trip to my parents).

Last edited by 9krpmrx8; 01-10-2011 at 06:02 PM.
Old 01-10-2011, 06:17 PM
  #6  
Registered User
iTrader: (2)
 
terch1's Avatar
 
Join Date: Feb 2008
Posts: 1,317
Likes: 0
Received 2 Likes on 2 Posts
Originally Posted by 9krpmrx8
Man, you are ambitious. This is not something I would do just to check things

For the price it's easier to just replace everything. I actually wish I could have done my injectors at that time but it was Christmas and I was low on funds. My fuel injectors have 120k on them as well so i am planning to get them cleaned and bench tested.
I was having a bitch of a time getting the omp and adapter to marry to the engine. So I unplugged the wiring harness from the omp and disconnected the feed lines so I could get everything to marry up properly. This project was a real pain in the ***. It would probably have been a hell of alot easier to do if the car was on a lift. I have pretty big hands and reaching some of the bolts to the omp was almost impossibe especially when reinstalling with the adapter. I pray to the gods that my omp never takes a crap on me.
Old 01-10-2011, 08:19 PM
  #7  
Time for boost...
iTrader: (24)
 
RX8Soldier's Avatar
 
Join Date: Jun 2010
Location: Canada
Posts: 5,414
Likes: 0
Received 15 Likes on 14 Posts
Hmmm this is all very interesting. I'm thinking about adding the SOHN adapter this spring. My 2007 only has 31k Kilometers (~19k miles). I'll make sure to check those lines!
Old 01-10-2011, 09:41 PM
  #8  
Registered
iTrader: (2)
 
GeorgeH's Avatar
 
Join Date: Oct 2003
Location: Portland OR
Posts: 1,666
Likes: 0
Received 3 Likes on 3 Posts
So, what would cause the oil lines to clog?
Old 01-10-2011, 09:52 PM
  #9  
The Stink w.o The Sause
iTrader: (5)
 
stinksause's Avatar
 
Join Date: Jun 2009
Location: North DE
Posts: 2,448
Likes: 0
Received 2 Likes on 2 Posts
subbed...
Old 01-10-2011, 10:40 PM
  #10  
Boosted Kiwi
iTrader: (2)
 
Brettus's Avatar
 
Join Date: Apr 2006
Location: Y-cat-o NZ
Posts: 20,523
Received 1,490 Likes on 839 Posts
Interesting . I don't rely on omp anymore anyway so ......
Old 01-10-2011, 11:42 PM
  #11  
SARX Legend
Thread Starter
iTrader: (46)
 
9krpmrx8's Avatar
 
Join Date: Jan 2007
Location: San Antonio, Texas
Posts: 33,784
Received 452 Likes on 366 Posts
TX

Originally Posted by terch1
I was having a bitch of a time getting the omp and adapter to marry to the engine. So I unplugged the wiring harness from the omp and disconnected the feed lines so I could get everything to marry up properly. This project was a real pain in the ***. It would probably have been a hell of alot easier to do if the car was on a lift. I have pretty big hands and reaching some of the bolts to the omp was almost impossibe especially when reinstalling with the adapter. I pray to the gods that my omp never takes a crap on me.

Oh ok so you didn't remove the OMP lines all together (you have to remove the intake manifold, etc.) Two of the OMP bolts I get from the top and one from the bottom. I have taken the SOHN and OMP off a couple of times so it is fairly easy. But I have pretty small hands so......

Originally Posted by GeorgeH
So, what would cause the oil lines to clog?
Not sure, on each of my engines, oil changes never went beyond 3,000 miles and for the last 20k or so they have seen nothing but pure, clean 2 stroke and Idemitsu.

OD said (have not verified) there is a check valve in the banjo fitting, maybe that was stuck closed? All I know is that I could blow through two of them and not the others. The lines were very dry rotted though after 120,000 miles so I'm not sure. I think it was a combination of the failed oil injector and the lines.

But comparing the new lines to my old ones was scary.
Old 01-11-2011, 12:48 AM
  #12  
i'm the undead
 
diabolical1's Avatar
 
Join Date: Jul 2004
Posts: 254
Likes: 0
Received 0 Likes on 0 Posts
this was pretty astute on your part and i commend it. whenever i go home and get back to my car (i can't wait ) i think i'll check my lines and jets as you suggested. it's of particular concern to me since i had stopped premixing months before i parked the car last January.
Old 01-11-2011, 12:51 AM
  #13  
Out of NYC
iTrader: (1)
 
nycgps's Avatar
 
Join Date: Jun 2005
Location: Planet Earth
Posts: 19,881
Received 32 Likes on 30 Posts
well 9k, just so u know on the rx7 side some people replace their OMP lines every 50-100K.

cuz its still f-ing plastic, and overtime it will degrade, dirt builds up, clog, and finally failed(burst/leak)

some people just replaced them with stainless steel lines, those never dies.

im Almost at 60K miles, gonna look at those when it gets warmer (tonight its like 24 degrees)
Old 01-11-2011, 01:35 AM
  #14  
Banned
iTrader: (3)
 
MazdaManiac's Avatar
 
Join Date: Oct 2003
Location: Under my car
Posts: 16,386
Likes: 0
Received 24 Likes on 21 Posts
How did you verify that the injector nozzles were, in fact, clogged?

I've never seen one get clogged. I have seen the check valve fail (that is pretty common), but it would only be an issue on a boosted motor.

Oil consumption should be very low on a highway trip. The commanded injection amount is very slight.
Even with the increased values I command in my AP tuning, I never see more than 1/8 of a quart per 300 miles of constant highway mileage.
I will go through 1/2 quart in 20 minutes on the track (about 15 miles, typically).
Old 01-11-2011, 02:37 AM
  #15  
Registered
iTrader: (1)
 
FazdaRX_8's Avatar
 
Join Date: Jun 2009
Posts: 2,019
Likes: 0
Received 5 Likes on 5 Posts
Can air get in these lines?
Is there a way to manually run the pump to see fluid moce through the lines?
Old 01-11-2011, 03:59 AM
  #16  
Super Moderator
 
ASH8's Avatar
 
Join Date: Apr 2005
Location: Australia
Posts: 10,861
Received 316 Likes on 225 Posts
So, basically my engine would have died eventually due to the lack of oil being injected had I not been premixing so heavy. My new theory is that many engines are dieing due to this and people are not even aware that this is the cause.
Glad you agree with what I have been saying for years, IMO not so much the amount of Metered Oil (still important) but where it is being distributed...or more importantly where not.

As you and many know this is the first time since 1985 that there was not a middle in Rotor Housing Oil Nozzle in a fuel injected rotary.

Frankly, I don't know why Mazda continues to use a poxy thin inside diameter tubing for MOP oil supply to nozzles, it is basically the same stuff they used for 40 years , the clear tube that is.
It can become brittle (heat), blocked and just old...very quickly.

Yeah, I like nycgps idea (7 club) of SS lines.
Old 01-11-2011, 09:31 AM
  #17  
SARX Legend
Thread Starter
iTrader: (46)
 
9krpmrx8's Avatar
 
Join Date: Jan 2007
Location: San Antonio, Texas
Posts: 33,784
Received 452 Likes on 366 Posts
TX

Originally Posted by MazdaManiac
How did you verify that the injector nozzles were, in fact, clogged?

I've never seen one get clogged. I have seen the check valve fail (that is pretty common), but it would only be an issue on a boosted motor.

Oil consumption should be very low on a highway trip. The commanded injection amount is very slight.
Even with the increased values I command in my AP tuning, I never see more than 1/8 of a quart per 300 miles of constant highway mileage.
I will go through 1/2 quart in 20 minutes on the track (about 15 miles, typically).

The oil injector just failed the vacuum test. It was the lines that were clogged (two of them). I could blow through two of the lines and two I could not. I knew something was definitley up during my last run through the canyons. Typically I would use 1/2 quart during the first half of the day after driving pretty hard through the canyons.
Old 01-11-2011, 09:48 AM
  #18  
Banned
iTrader: (3)
 
MazdaManiac's Avatar
 
Join Date: Oct 2003
Location: Under my car
Posts: 16,386
Likes: 0
Received 24 Likes on 21 Posts
There are check valves in the lines as well.
Old 01-11-2011, 09:48 AM
  #19  
SARX Legend
Thread Starter
iTrader: (46)
 
9krpmrx8's Avatar
 
Join Date: Jan 2007
Location: San Antonio, Texas
Posts: 33,784
Received 452 Likes on 366 Posts
TX

Originally Posted by ASH8
Glad you agree with what I have been saying for years, IMO not so much the amount of Metered Oil (still important) but where it is being distributed...or more importantly where not.

As you and many know this is the first time since 1985 that there was not a middle in Rotor Housing Oil Nozzle in a fuel injected rotary.

Frankly, I don't know why Mazda continues to use a poxy thin inside diameter tubing for MOP oil supply to nozzles, it is basically the same stuff they used for 40 years , the clear tube that is.
It can become brittle (heat), blocked and just old...very quickly.

Yeah, I like nycgps idea (7 club) of SS lines.

While replacing this stuff I was thinking the same thing. Why plastic tubes? SS lines would last forever.
Old 01-11-2011, 10:21 AM
  #20  
SARX Legend
Thread Starter
iTrader: (46)
 
9krpmrx8's Avatar
 
Join Date: Jan 2007
Location: San Antonio, Texas
Posts: 33,784
Received 452 Likes on 366 Posts
TX

Originally Posted by MazdaManiac
There are check valves in the lines as well.

Yeah I am wondering if the check valves in the two lines were stuck or if the actual line itself was clogged. But I couldn't blow through two of them.
Old 01-11-2011, 10:38 AM
  #21  
Out of NYC
iTrader: (1)
 
nycgps's Avatar
 
Join Date: Jun 2005
Location: Planet Earth
Posts: 19,881
Received 32 Likes on 30 Posts
Originally Posted by ASH8
Glad you agree with what I have been saying for years, IMO not so much the amount of Metered Oil (still important) but where it is being distributed...or more importantly where not.

As you and many know this is the first time since 1985 that there was not a middle in Rotor Housing Oil Nozzle in a fuel injected rotary.

Frankly, I don't know why Mazda continues to use a poxy thin inside diameter tubing for MOP oil supply to nozzles, it is basically the same stuff they used for 40 years , the clear tube that is.
It can become brittle (heat), blocked and just old...very quickly.

Yeah, I like nycgps idea (7 club) of SS lines.
yep, this is why im thinking maybe I should get some of those, cut & fit them myself.
Old 01-11-2011, 12:11 PM
  #22  
BearBlasterExtraordinair!
iTrader: (3)
 
Beodude's Avatar
 
Join Date: Nov 2010
Location: Haughton, Louisiana
Posts: 731
Likes: 0
Received 3 Likes on 2 Posts
Has any company made SS lines for the oil injectors? I've never tried to make them before, but I know it can be done.
Old 01-11-2011, 01:21 PM
  #23  
Registered
iTrader: (3)
 
olddragger's Avatar
 
Join Date: Apr 2004
Location: macon, georgia
Posts: 10,828
Likes: 0
Received 38 Likes on 27 Posts
what is the purpose of the check valve in the banjo fitting? Doesnt the oil "injector" have its own?
Seems like overkill to me?

By the way--good thread
OD
Old 01-11-2011, 01:56 PM
  #24  
Registered
iTrader: (1)
 
FazdaRX_8's Avatar
 
Join Date: Jun 2009
Posts: 2,019
Likes: 0
Received 5 Likes on 5 Posts
During the very first part of compression maybe air could get in oil lines, so they put in a check valve so only oil goes out, after reading this thread I looked at my lines, and noticed air bubbles. Also I switched to rp a while ago but the lines are still light brown, not dark like rp, an illiusion?

I am glad I am premixing
Old 01-11-2011, 02:22 PM
  #25  
Out of NYC
iTrader: (1)
 
nycgps's Avatar
 
Join Date: Jun 2005
Location: Planet Earth
Posts: 19,881
Received 32 Likes on 30 Posts
Originally Posted by Beodude
Has any company made SS lines for the oil injectors? I've never tried to make them before, but I know it can be done.
plug & play nope.

need to make your own.


You have already rated this thread Rating: Thread Rating: 1 votes, 5.00 average.

Quick Reply: Possible New Renesis Engine Failure Theory?



All times are GMT -5. The time now is 10:30 PM.